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21.
A paralysis of the left vocal cord was seen by laryngoscopy in a 3-days-old boy with inspiratory stridor. A ductus aneurysm was established by angiocardiography, which was believed to be the cause of the vocal cord paralysis. Within 8 days after the angiocardiography the aneurysm became smaller and the stridor disappeared. Twelfth months later the control-angiocardiography showed the total obliteration of the ductal aneurysm. 相似文献
22.
T Groth C Vassilieff H Wolf G Richter F Foerster 《Journal of biomaterials science. Polymer edition》1992,3(4):285-300
In this study a new dynamic method is introduced allowing the estimation of blood cell adhesion on flat test surfaces by measuring the cell loss in the bulk phase of surface contacting test blood under defined rheological conditions. This was achieved by constructing a novel test chamber permitting the contact of small amounts of blood with a large geometrical test surface. The construction consists of a spiral-shaped flow channel of 0.3 cm width, 0.02 cm height and 78 cm length covered with the biomaterials to be tested from both sides. Laminarity of blood flow in the conduit was confirmed theoretically by the calculation of an equivalent to the Reynolds number for curved systems the so-called Dean number. Furthermore, flow laminarity was proved experimentally finding that the flow rate of blood with different hematocrit values was proportional to the hydrostatic pressure applied. The applicability of the novel 'spiral method' for the estimation of hemocompatibility was demonstrated by evaluation of platelet adhesion onto different polymers in comparison to siliconized and fibrinogen coated glass as reference surfaces. Additionally, it was possible under distinct conditions to determine the adhesion of leucocytes and the detachment of platelet aggregates. Therefore, it was concluded that the spiral method can be used for the assessment of the hemocompatibility of flat biomedical polymers. As main advantages of the new method can be considered the high time efficiency and accuracy without labelling or optical detection of adherent cells. 相似文献
23.
The disaccharidase activities of the mucous membrane of the small intestine were determined in formerly hypotrophic children who showing a dystrophy with a morphological normal mucosa (n = 36), patients with a flat mucosa caused by enteral protein intolerances of different genesis (n = 27), patients with a morphologically and functionally normal mucosa (n = 51). In about half of the former small-for-date children were shown activities lower than the simple standard deviation of the normal value, for lactase n = 17, for sucrase n = 14, for maltase n = 12. Some children showed pathologically reduced activities even below the double standard deviation for the normal value: lactase n = 8, sucrase n = 5, maltase n = 3. 相似文献
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Gresham T Richter Jacob E Smith Horace J Spencer Chun Y Fan Emre Vural 《Otolaryngology--head and neck surgery》2007,137(2):239-242
OBJECTIVES: Histological comparison of human-based (AlloDerm) and porcine-based (ENDURAGen) dermal matrices regarding tissue incorporation and neovascularization as potential soft tissue augmentation materials. STUDY DESIGN: In vivo, rat model. METHODS: Subcutaneous implantation of 1-mm thick, 1 cm x 1 cm pieces of AlloDerm, ENDURAGen, and meshed ENDURAGen was performed in 24 Sprague Dawley rats. Implant materials were harvested at 4 (n = 12) and 8 weeks (n = 12). Histological quantification of soft tissue ingrowth and microvascular density was performed following hematoxylin-eosin staining and CD34 immunohistochemistry, respectively. RESULTS: AlloDerm showed significantly greater soft tissue ingrowth and microvascular density compared with both ENDURAGen and meshed ENDURAGen at 4 and 8 weeks (P < 0.001). CONCLUSIONS: Although these results may differ in human host tissues, AlloDerm seems to be a more suitable dermal matrix implant than ENDURAGen for cases in which tissue incorporation and neovascularization are sought for the optimal outcome based on this animal model. 相似文献
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In a previous study a high first-pass metabolism of N-nitrosodi-[1-14C]butylamine(NDBA, O.32730p.µM) has been shown in isolatedperfused rat small intestinal segments. In the present workthe identification and quantitation of metabolitesin samplesof perfusate and absorbed fluid (absorbate) is reported. AfterHPLC enrichment and purification five metabolites could be identifiedby GLC-MS: N-nitrosobutyl-(3-hydroxybutyl)amine (NB3HBA), N-nitrosobutyl-(4-hydroxybutyl)amine(NB4HBA), N-nitrosobutyl-(3-carboxypropyl)amine (NB3CPA), N-nitrosobutyl-(2-hydroxy-3-carboxypropyl)amine(NB2H3CPA) and N-nitrosobutylcarboxymethylamine (NBCMA), representing> 95% of total metabolites. -hydroxylatlon leading to NB4HBAand NB3CPA accounted for 7595% of total metabolites.The formation of their follow-up products NB2H3CPA and NBCMAwas too small for quantitative analysis. In absorbate NB3CPAwas by far the most important metabolite. The hydroxylationof NB4HBA to NB3CPA was more efficient in jejunal as comparedto ileal segments.-1-hydroxylation to NB3HBA and, as reportedpreviously, -hydroxylation were only minor metabolic pathways.In conclusion, a high first-pass metabolism of NDBA to the proximatebladder carcinogen NB3CPA takes place during its absorptionin rat small intestine. This is in contrast to the observationin rat liver preparations, where - and -1-hydroxylation arethe predominant pathways. The intestinal first-pass metabolismmay play a key role explaining the increased incidence of bladdertumors in rats after low oral doses of NDBA. 相似文献
28.
Müller G Richter RA Weisbrod S Klingberg F 《Archives of gerontology and geriatrics》1992,14(3):215-225
Tactile pattern recognition of ten different patterns which were engraved upon 4 x 4 cm plastic plaquettes with one hand and thereafter drawing with the other or the same hand was tested in 21 patients with a mild stage primary degenerative presenile onset dementia of Alzheimer type (DAT) and in 14 patients with a questionable dementia on the background of a chronic cardiovascular disease (CVD) in comparison to 15 healthy subjects of the same age (51 years old, elder controls, (EC)) and 16 younger subjects (22 years old, younger controls, (YC)). Patients made about four times more errors than the EC group. Duration from the begin of touching to the end of drawing was significantly longer in patients than in controls. In a second task the subjects had to recognize four subsequent patterns, then to perform a standard multiplication task and afterwards to draw all four patterns in their correct sequence. Patients made about ten times more errors in pattern recognition and series reproduction than age-matched controls. 相似文献
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Herpes simplex virus (HSV) type 1 replicated and persisted in human T, B, and myeloid cell lines with different patterns of viral replication and various effects on cell growth. T cell line CEM supported the replication of HSV for over 400 days without detectable differences in cell growth as compared with uninfected cells. HSV persisted in B cell line NC37 and myeloid cell line K562 for up to 222 and 374 days, respectively, but led to a significant decrease in the number of viable cells by 7 weeks of infection. The average number of cells producing infectious virus was very low in these cell lines (range, 0.5 to 2.7+) compared with a larger proportion of cells exhibiting HSV antigens by immunofluorescence (range, 24 to 58%). In contrast, null cell line LAZ 221 failed to replicate HSV even though the viral infection led to a cessation of cell growth. 相似文献